Maintaining a branch for every environment is extremely complex and error prone. All the branching strategies you see are always about main because it's simpler

Maintaining a branch for every environment is extremely complex and error prone. All the branching strategies you see are always about main because it's simpler. Ensure the code merged into the main branch is always in a working state and you don't need to have a complex branching strategy. This requires stricter testing practices in the PRs, and usually also involves either requiring PRs to be up to date with master prior to merge, or re-testing of master after merge, prior to the SHA being deployable.